- Huang Qin
- baikal skullcap
- Chinese skullcap
For Patients & Caregivers
Bottom Line: Scutellaria baicalensis has been used in traditional medicine to treat many medical conditions. Studies on its anticancer effects are underway.
Scutellaria baicalensis, also known as Huang Qin or Chinese skullcap, is a root extract used in traditional medicine, often in combination with other herbs. Scientists are not sure exactly how it works; it has been studied to some extent in the laboratory, but not in humans. Isolated liver cancer and leukemia cell lines, when exposed to extracts from this herb, undergo apoptosis (cell death). The extracts also reduce inflammation, act as antioxidants, and kill gram-positive bacteria in the laboratory setting. In animals, the extracts help lower blood cholesterol levels under certain conditions. However, it is not yet clear if any of these effects occur in the human body.
- To treat atherosclerosis
Studies in animals show that extracts of this herb may help lower blood cholesterol levels under certain conditions, but human studies have not been conducted.
- To treat cancer
Extracts from this herb cause cell death in isolated liver cancer and leukemia cell lines in the laboratory setting, but human data are lacking.
- To treat hepatitis
The herbal formulation sho-saiko-to, which contains Huang Qin, has been studied for its possible liver-protectant effects.
- To treat arthritis
An herbal supplement containing S. baicalensis has been shown to reduce symptoms of osteoarthritis. It is not known if the herb would exert similar effects by itself.
- You are taking warfarin or other blood thinners (skullcap can increase the risk of bruising and bleeding).
- You are on statins (skullcap can decrease the blood level of these drugs).
- If you are taking drugs that are substrates of Cytochrome P450 (skullcap may increase the risk of side effects of these drugs).
For Healthcare Professionals
Scutellaria baicalensis is an herb used in traditional Chinese medicine to treat a variety of conditions including epilepsy, hepatitis, infections, and cancer. It often is used in combination with other botanicals (e.g. PC-SPES and Sho-saiko-to).
In vitro and animal data suggest that its components cause apoptosis in various cancer cells (2)(3)(14), demonstrate neuroprotective (4)(5) and anti-inflammatory (17) effects, and protect against doxorubicin-induced cardiotoxicity (15). In addition, sedative and anticonvulsant effects have also been reported (6).
An herbal supplement containing S. baicalensis has been shown to reduce symptoms of osteoarthritis (22). It is not known if the herb would exert similar effects by itself.
Baicalin exhibits anti-inflammatory, antioxidant, and gram-positive antibacterial activity in vitro (3). It was also shown to attenuate important features of asthma, possibly by reducing airway injury and restoring mitochondrial function (19). The neuroprotective effects of flavonoids were ameliorated by diazepam, a GABA receptor agonist, suggesting that the components influence GABA receptor activity (5). The flavonoids also prevent ethanol-induced hyperlipidemia, histamine release from mast cells, and catecholamine-induced lipolysis in animal models (8).
In vitro studies suggest that flavonoid components of S.baicalensis have anticancer activity. Induction of apoptosis in hepatoma G2, 3B, and SK-Hep1 cell lines occurs following 48 hours of exposure to baicalein, baicalin, and wogonin at concentrations of 25-100 mcg/ml. Wogonin causes arrest at G1 phase while baicalin and baicalein cause G2/M accumulation (2). Additional studies show that baicalin, at concentrations of 50-200 mcg/ml, activates caspase-3, resulting in apoptosis of Jurkat cells (leukemia-derived T cells).
Urinary pharmacokinetic analysis of baicalein, wogonin, and their glycosides in humans indicated that excretion of conjugated metabolites of wogonin was greater than those of baicalein (11.6 versus 7.2% of the dose) (10). The low recovery of both compounds may be due to bile excretion or metabolism by enteric bacteria. In addition, in vitro studies revealed that baicalein is capable of crossing the gut epithelium as well as the blood-brain barrier (11).
- Anticoagulants / Antiplatelets: May cause additive effects (12).
- Statins: Baicalin, an active constituent, can decrease the blood level of statin drugs used to lower cholesterol (13).
- Cytochrome P450 substrates: Wogonin inhibits CYP1A2 and CYP2C19, and can affect the intracellular concentration of drugs metabolized by these enzymes (16).
- Dextromethorphan: Baicalin was shown to inhibit metabolism of dextromethorphan in rats possibly via inhibition of hepatic CYP2D and CYP3A (20).
- Solute carrier (SLC) transporters: Baicalein, baicalin, and wogonin inhibit uptake of specific substrates mediated by essential SLC transporters, which are important membrane proteins responsible for the cellular influx of various drugs (21).